Road sweeper suction hood draft connection

ABSTRACT

In a road sweeper employing a suction hood carried by caster wheels beneath the sweeper frame, the hood has a draft connection with the frame employing a suspended transverse shaft so connected to the hood structure as to maintain it in centered position while allowing the hood vertical displacements and limited lateral oscillations.

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rte ates till 1 1 3, 3 Larsen 5] .llan. W, 1972 [54] ROAD SWEEPEIR SUCTION H001) 3,007,191 11/1961 Braun ..15 340 DRAFT CONNECTKUN 3,189,932 6/1965 Daneman ..15/340 [72] Inventor: Gregory J. Larsen, Claremont, Calif. FOREIGN PATENTS OR APPLICATIONS Assignee: Wayfne Manufacturing Company, P 29,456 12/1909 Great Britain 15/340 Cali 22 Filed: Nov. 13 19 9 Primary Examiner-Walter A. Scheel Assistant Examiner-C. K. Moore [21] PP 376,440 Attorney-White&l-laefliger 52 us. (:1 ..15/340, 280/460 ABSTRACT g g 52 i In a road sweeper employing a suction hood carried by caster 1 l9 0 46-0. wheels beneath the sweeper frame, the hood has a draft con l nection with the frame employing a suspended transverse [56] References Cited shaft so connected to the hood structure as to maintain it in centered position while allowing the hood vertical displace- UNITED STATES PATENTS ments and limited lateral oscillations. 265.5 39 10/1882 Riddle ..94/50 R 7 Claims, 5 Drawing Figures ROAD SWEEPER SUCTION lI-IOOlD DRAFT CONNECTION BACKGROUND OF THE INVENTION In road sweepers of the type employing a suction hood carried by swivel casters beneath the sweeper frame, difficulties have arisen in attempting to maintain the hood centered below the longitudinal axis of the sweeper vehicle while allowing for both vertical displacement and lateral oscillation of the hood about its axis in accordance with road conditions. Where the hood has flexible connections with a suction source, control of the hood movements must be compatible with flexure ranges of such connections.

SUMMARY OF THE INVENTION This invention has for its general object to provide a simply constructed draft connection to a three wheel supported suction hood, which will assure constant centered position of the hood against draft tendencies attributable to its caster support while allowing for vertical displacement and limited lateral oscillation of the hood.

Structurally the invention contemplates accomplishment of this objective by a hood draft connection employing a shaft suspended forwardly of the hood and having arm connections therewith operable, as will appear, to maintain and allow the stated hood position and movements under road sweeping conditions For more complete explanation and understanding of the invention, reference is had to the illustrative embodiment shown by the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing in side elevation a suction hood type road sweeper embodying the invention;

FIG. 2 is fragmentary enlargement showing in solid line the suction hood in elevated position and in broken lines the hood in lowered sweeping position;

FIG. 3 is an enlarged fragmentary section on line 33 of FIG. 2;

FIG. 4 is a fragmentary plan view of the suction hood and its draft connection taken on broken line 4-4 of FIG. 2; and

FIG. 5 is an illustration in perspective of the transverse draft shaft and its hood connecting arms.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIG. 1, the four-wheel sweeper truck is shown to have a frame structure which mounts a debris chamber 11 pivoted at 12 for rear dumping. Suction is communicated to the chamber from a motor driven blower through conduit 13 and suction-induced entrainment of debris into the chamber occurs through a conduit series generally indicated at 14 and comprising upper rigid sections 15 and lower flexible or hose sections 16,1611 with joints at 17 between the sections operable to open and close as the chamber 11 is swung from dumping position to the normal position shown in FIG. 1. The hose sections 16 and 16a communicate with an open bottom suction hood 18 by way of connections 19 and 20 extending upwardly from the hood. The latter contains a cylindrical pickup broom 21 driven by motor 22 to sweep and displace debris forwardly for passage through the conduits 19 and 20. The details of the suction hood and associated parts are more particularly dealt with in my copending application Ser. No. 878,325 entitled RUNWAY OR STREET SWEEPER having common assignee with this application.

During sweeping operations suction hood 18 is supported by a forward wheel 24 centered below and in alignment with the truck frame axis, this forward wheel being supported from the front transverse hood frame member 241 between arms 24a. At its rear the hood is carried by a pair of caster wheels 25 positioned below and at opposite sides of the frame axis, these wheels being carried by arms 26 pivoted at 27 to the rear transverse hood frame member 242. The wheels 25 may e suitably held as by stabilizers 28 against excessive lateral oscillations.

The invention is primarily concerned with the suction hood draft connection generally indicated at 30 and which is suspended from the truck frame members 10. As illustrated in FIG. 4 the draft assembly 30 is shown to comprise a transverse shaft 31 spaced forwardly from the hood frame member 241 and carried by the truck frame suspensions 32 with their inclined braces 33. The suspension terminals mount bearing plates 34 which receive the shaft terminals 35 and thus support the shaft for limited oscillation. Rigidly fixed to the shaft is a first arm 36 given additional support by the diagonal brace 37 and connected to the frame member 241 by pivotal joint 38. The opposite end of shaft 31 is provided at 40 and at the inside of spacer 41 to a second arm 42 pivotally joined at 43 to the frame member 241.

By virtue of its rigid connection to the shaft 31 arm 36 serves to maintain the suction hood centered beneath the truck frame while allowing vertical displacements of the hood by reason of the pivotal connection at 38. The arm 42 connection at 40 with the shaft 31 may be a closely fitted association of the shaft with the arm allowing little or no looseness in the connection. However the pivotal connections at 38 and 43, see FIG. 3, are purposely made loose, e.g., as to the arms 36 and 42, so as to afford the latter limited displacement relative to the pivots 45 and between the mounting arms 46. The purpose of providing for such looseness in these pivotal connections is to allow for limited lateral movements or oscillation of the hood 18 within the ranges of restraint imposed by the pivots. Thus the draft assembly 30 performs the combined functions of maintaining the hood in properly centered posi tion while allowing limited lateral drift tendencies which the hood may have by reason of its rear caster wheel mounting.

As shown in FIG. 2 the hood and its frame structure may be elevated for nonsweeping travel by suitable mechanism carried by the truck chassis. As illustrative, the lifting mechanism is shown to comprise forward and rear suspension cables 47 and 48 connected at 49 and 50 to the hood, the cables being connected to bell crank 51 rotatable about pivot 52 and actuated by piston 53. The hood is limited in its lifted position by the engagement of bumper 54 against the underside of the frame 10.

I claim:

1. In combination with a four wheel road sweeper having a frame, a rotary pickup broom-containing open bottom suction hood underlying the frame and supported by a single forward wheel centered transversely of the frame and by a pair of rear caster wheels at opposite sides of the frame transverse center, a draft connection to the hood comprising a transverse shaft mounted to the frame forwardly from the hood for limited axial oscillation in response to vertical hood displacements, a pair of arms extending from the shaft and having pivotal connections to the hood, a first of said arms being rigidly joined to the shaft to maintain centering of the hood and the second arm being pivoted to the shaft, said transverse shaft defining a first pivot axis that is generally horizontal and normal to the direction of sweeper forward travel, and the arm pivotal connections to the hood defining a second pivot axis generally parallel to the first pivot axis, the second axis being movable up and down in response to up and down displacement of the hood relative to the frame, and means carried by the frame to displace the hood between an elevated position for nonsweeping travel and a down position in which said forward wheel and a rotary broom engage the road surface.

2. The combination of claim 1, in which said first arm is supported to the shaft by a diagonal brace.

3. The combination of claim 1, in which said pivotal connections have predetermined looseness to allow for limited lateral oscillations of the hood.

4. The combination of claim 1, including braced shaft suspension members depending from the sweeper frame.

5. The combination of claim 1, in which said arms are connected to the upper front of the hood structure.

6. The combination of claim 3, in which said arms are connected to the upper front of the hood structure.

7. The combination of claim 3, in which said hood has association with flexible suction conduits subject to flexure in response to said hood oscillations. 5 

1. In combination with a four wheel road sweeper having a frame, a rotary pickup broom-containing open bottom suction hood underlying the frame and supported by a single forward wheel centered transversely of the frame and by a pair of rear caster wheels at opposite sides of the frame transverse center, a draft connection to the hood comprising a transverse shaft mounted to the frame forwardly from the hood for limited axial oscillation in response to vertical hood displacements, a pair of arms extending from the shaft and having pivotal connections to the hood, a first of said arms being rigidly joined to the shaft to maintain centering of the hood and the second arm being pivoted to the shaft, said transverse shaft defining a first pivot axis that is generally horizontal and normal to the direction of sweeper forward travel, and the arm pivotal connections to the hood defining a second pivot axis generally parallel to the first pivot axis, the second axis being movable up and down in response to up and down displacement of the hood relative to the frame, and meAns carried by the frame to displace the hood between an elevated position for nonsweeping travel and a down position in which said forward wheel and a rotary broom engage the road surface.
 2. The combination of claim 1, in which said first arm is supported to the shaft by a diagonal brace.
 3. The combination of claim 1, in which said pivotal connections have predetermined looseness to allow for limited lateral oscillations of the hood.
 4. The combination of claim 1, including braced shaft suspension members depending from the sweeper frame.
 5. The combination of claim 1, in which said arms are connected to the upper front of the hood structure.
 6. The combination of claim 3, in which said arms are connected to the upper front of the hood structure.
 7. The combination of claim 3, in which said hood has association with flexible suction conduits subject to flexure in response to said hood oscillations. 